introduce NETIF_F_GSO_ENCAP_ALL helper mask

part of commit f6eec614 upstream.

Add NETIF_F_GSO_ENCAP_ALL mask covering all encapsulation GSO flags.

[mk] only introduce the helper, do not pick the openvswitch change the
original commit was about.
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Acked-by: Andy Zhou <azhou@nicira.com>
Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>

include/linux/netdev_features.h

@@ -157,4 +157,8 @@ enum {
 /* changeable features with no special hardware requirements */
 #define NETIF_F_SOFT_FEATURES	(NETIF_F_GSO | NETIF_F_GRO)
 
+#define NETIF_F_GSO_ENCAP_ALL	(NETIF_F_GSO_GRE |			\
+				 NETIF_F_GSO_UDP_TUNNEL |		\
+				 NETIF_F_GSO_MPLS)
+
 #endif	/* _LINUX_NETDEV_FEATURES_H */